Refrigeration



Sept. 24, 1940. H. M. ULLSTRAND REFRIGERATION Filed Jan. 4, 1958 IN ENTOR. W M;

9 6! i z, 4 ATTORNEY.

Patented Sept. 24, 1940 UNITED. STATES PATENT OFFICE- A REFRIGERATION Servel, Inc., New York, N. Y., a corporation of Delaware Application January 4, 1938, Serial No. 183,257

6 Claims.

My invention relates to an absorption type refrigeration system and it is an object of this invention to provide a system of this type which has a higher efllciency.

The single figure of the drawing shows more or less diagrammatically an absorption refrigeration system of the type making use of an auxiliary pressure equalizing fluid and embodying the invention.

A generator I!) is heated by a gas burner l l arranged so that the flame projects into the lower end of flue l2 which extends upward through the generator. Any other suitable heater may be used as, for instance, an electric heating elell ment or a liquid fuel burner.

An absorber l3 and an evaporator l 4 are interconnected by members including a gas heat exchanger l5. The evaporator It comprises a coil located in a refrigerator compartment IS. The absorber l3 comprises a coil provided with heat transfer fins for air cooling and a sump or pot Ho. The absorber may be cooled in any other suitable manner as by circulating water or a vaporization-condensation heat transfer circult.

The absorber l3 and generator H) are interconnected by members including a triple heat exchanger ll. The generator I 0 is connected by 80 members also including the heat exchanger H to an air cooled condenser l8 and the condenser la is connected to the evaporator IA. The connections are hereinafter described in connection with the operation of the system.

35 The system contains a refrigerant fluid such as ammonia, a liquid absorbent such as water, and an auxiliary pressure equalizing fluid such as hydrogen.

In operation, vapors are expelled by heating 0 of solution in the generator Ill. The vapors flow from the generator through a conduit Hi, the outside passage of the heat exchanger IT, a conduit 2|, a vessel 22, a conduit 23, a vessel 24, and a conduit to the upper end of the con- 45 denser l8. Ammonia vapor condenses to liquid in the condenser I8 and the liquid ammonia flows from the lower end of the condenser through a conduit 26 to the upper end of the evaporator l4. Liquid ammonia flows downward in the evapo- 50 rator l4 and evaporates and diffuses into the hydrogen, producing a refrigerating efiect. The mixture of hydrogen gas and ammonia vapor, referred to as rich or strong gas, flows from the upper end of the evaporator through conduit 21,

55 the inner passage 28 of the gas heat exchanger AUG 2 4 1945 I5, and a conduit 29 to the lower part of absorber l3.

Weakened solution flows from the generator l0 through a conduit 30, the inner passage 3! of the heat exchanger I7, and a conduit 32 into the upper part of the absorber l3. weakened solution flows downward in absorber I3 and absorbs ammonia vapor out of the gas. Weak or poor gas flows from the upper part of the absorber I3 through conduit 33, the outer passage 32 of the 10 gas heat exchanger I5, and conduit 35 back to the lower end of evaporator l2.

Enriched absorption liquid, referred to as strong or rich solution, flows from the lower part of absorber I3 through a conduit 36, vessel 22, 15 conduit 23, vessel 24, a conduit 3?, the middle passage 38 of the heat exchanger I l, and conduit 39 into the generator in.

Weak solution flowing through inner passage 3! of the heat exchanger ll transfers heat to 2 strong solution flowing in the opposite direction through the middle passage 38 of the heat exchanger, whereby the weak solution is cooled and the heat is added to the strong solution and returned thereby to the generator I0. Heat is 25 also transferred to the strong solution from vapors flowing in the outside passage 20 of the heat exchanger ll. This cooling of the vapors is attained by condensation of water vapor to liquid and is referred to as rectification. The condensate drains from the lower end of the outside heat exchanger passage 20 through a conduit 40 into vessel 22. Any ammonia vapor that may be condensed in the outside passage 20 also drains through conduit 40 to the vessel 35 22. The condensate joins strong solution in vessel 22 and is returned therewith to the generator in the previously described path of flow. Heat of rectification transferred from vapor to strong solution in the heat exchanger I1 is returned with 40 the strong solution to the generator l0 so that this heat is not dissipated but is conserved.

Vapor passing from conduit 2| through vessel 22 into conduit 23 has to pass through liquid con-. tainecl in vessel 22 so that liquid is raised by vapor through conduit 23 into the circulation vessel 24.

The lower end of conduit 23 within vessel 22 may be provided with a hole 4|, as shown. Vapor entering vessel 22 causes liquid therein to be depressed to the level of hole 45 whereupon the vapor enters the hole 4! and flows upward in the conduit 23. Due to a head of liquid in conduit 36 and the lower part of absorber l3, liquid also enters the hole El alternately with the gas so that there is formed in conduit 23 a column comprising slugs of liquid separated by rising. pockets of gas. This column extending to the top of conduit 23 is balanced-by the liduid column or head of liquid in conduit 36 and lower part of absorber it. In the upper end of conduit 23, the liquid and gas emerge into vessel ,2'4 where the liquid drops down and the vapor continues on through conduit 28 to the condenser l8. Liquid rises in vessel 24 until the level of liquid in this vessel. stands above the level of liquid in the generator III a distance equal to the height of the surface level of liquid in the absorber ll above the hole ll in the lower end of conduit 23, whereupon liquidfiows in the previously described path from vessel II into the generator l0. Ananalyzing eilect is obtained by the bubbling of vapor through strong solution in passing through vessel 22 and the vapor lift conduit 23.

Various modifications and changes may be made within the scope of the invention which is not limited except as indicated in the following claims.

What is claimedis:

' 1. In an absorption refrigeration system, a generator, 'a rectifier, an absorber, and a vapor liquid lift for causing circulation of absorption liquid between said generator and absorber, said rectifier being arranged for cooling thereof by absorption liquid fiowing toward the said gen-" erator, and said lift being connected .to said absorber and said rectifier and said generator to receive liquid from both said absorber and rectifier, and vapor from said generator.

2. A system as set forth in claim 1 in which the generator vapors fiow first through said rectifierandthentosaidlift.

- connected to said rectifier to receive both con- 8. In an absorption refrigeration system, a generator, a rectifier, an absorber, a liquid heat exchanger connected between said generator and absorbensaid rectifier being in heat transfer relation with said exchanger, and a vapor liquid lift for causing circulation of absorption liquid between said generator and absorber through said exchanger, said lift being connected to receive liquid from both absorber andrectifier and vapor from said generator. I

4. An absorption refrigeration system including a generator, a rectifier for vapor from said generator connected to said generator and arranged to be cooled by absorption liquid flowing to said generator, and an analyzer in which the vapors from said generator fiow and contact with absorption liquid fiowing to said generator and which is connected to the rectifier to receive both condensate and vapor from said rectifier.

5. An absorption refrigeration system including a generator, a rectifier for vapors from said generator connected to said generator and arranged to be cooled by absorption liquid flowing towards said generator, and a vapor liquid lift densatean'd vapor from said rectifier.

6. An absorption refrigeration system including a generator, an absorber, a rectifier for vapors from said generator connected to said generator and arranged to be cooled by absorption liquid flowing from said absorber towards said generator, and a vapor liquid lift for causing said fiow connected to said absorber and said rectifier to receive vapor from said rectifier and liquid from both said absorber and rectifier.

HUGO M. UILBTRAND. 

